Ok so here's some background info on the car its a 2000 GXE it has 171,000 miles and the Alternator was just replaced a year ago and the radiator was replaced last month, also I just put a new battery in it back in May, also the car has an evap issue, I need to replace the valve cover gaskets. Well on monday I was driving my car to work and all of a sudden my airbag light began to blink so did my seat belt light so i pulled in to a nearby parking lot turned the car off tried to start it and it wouldn't start. I called my mechanic and he couldn't jump it and got it towed to his shop and fixed it for $195 dollars he told me that he needed to replace the negative wire connected to the battery he also said that my battery was to small. So he also put a new battery in. Well today I was driving down I-90 to my families house for turkey day and the airbag light started to blink again so did the seat belt light. Also somethin new was the car would start to jerk while driving it at about 70 also the gears weren't shifting properly. Well I get off at my exit and the car then stalls and I couldn't get it started again. Someone passing by was able to jump my car and it only lasted for about 10miles before dying again. I really need help with this I don't have enough money to keep spending on this car and I still owe 4 more months of payment. Does anyone know what the problem could be?